Display options
Cite
Nazario GM, Lovatt CJ. Separate de Novo and Salvage Purine Pools Are Involved in the Biosynthesis of Theobromine but Not Caffeine in Leaves of Coffea arabica L. Plant Physiol. 1993;103(4):1203-1210doi: 10.1104/pp.103.4.1203.
Nazario, G. M., & Lovatt, C. J. (1993). Separate de Novo and Salvage Purine Pools Are Involved in the Biosynthesis of Theobromine but Not Caffeine in Leaves of Coffea arabica L. Plant physiology, 103(4), 1203-1210. https://doi.org/10.1104/pp.103.4.1203
Nazario, G. M., and Lovatt, C. J.. "Separate de Novo and Salvage Purine Pools Are Involved in the Biosynthesis of Theobromine but Not Caffeine in Leaves of Coffea arabica L." Plant physiology vol. 103,4 (1993): 1203-1210. doi: https://doi.org/10.1104/pp.103.4.1203
Nazario GM, Lovatt CJ. Separate de Novo and Salvage Purine Pools Are Involved in the Biosynthesis of Theobromine but Not Caffeine in Leaves of Coffea arabica L. Plant Physiol. 1993 Dec;103(4):1203-1210. doi: 10.1104/pp.103.4.1203. PMID: 12232013; PMCID: PMC159107.
Copy Download .nbib Format: NLM
Share it on

Plant Physiol. 1993 Dec;103(4):1203-1210. doi: 10.1104/pp.103.4.1203.

Separate de Novo and Salvage Purine Pools Are Involved in the Biosynthesis of Theobromine but Not Caffeine in Leaves of Coffea arabica L.

Plant physiology

G. M. Nazario, C. J. Lovatt

Affiliations

  1. Department of Botany and Plant Sciences, University of California, Riverside, California 92521-0124.

PMID: 12232013 PMCID: PMC159107 DOI: 10.1104/pp.103.4.1203

Abstract

In Coffea arabica leaves, the purine ring of theobromine (3,7-dimethylxanthine) and caffeine (1,3,7-trimethylxanthine) is provided by de novo purine biosynthesis: (a) [14C]glycine, [14C]bicarbonate, and [14C]formate were incorporated into inosine 5[prime]- monophosphate (IMP), sum of adenine nucleotides ([sigma]Ade), theobromine, and caffeine; and (b) incorporation of [14C]formate into IMP, [sigma]Ade, theobromine, and caffeine was inhibited by azaserine, a known inhibitor of de novo purine biosynthesis. Capacity of coffee leaves to salvage added purines was demonstrated by incorporation of [14C]hypoxanthine into [sigma]Ade and the incorporation of [14C]adenosine, [14C]adenine, [14C]inosine, and [14C]hypoxanthine into both theobromine and caffeine. Consistent with synthesis of theobromine from two separate purine nucleotide pools, one synthesized de novo and one via salvage, added xanthine 5[prime]-monophosphate (XMP), inosine, or hypoxanthine failed to reduce the incorporation of [14C]formate into theobromine but diluted the specific radioactivity of [14C]adenosine and [14C]adenine incorporated into theobromine. Evidence that theobromine is not the immediate precursor of caffeine is provided: (a) [14C]xanthine was incorporated into caffeine but not into theobromine; (b) exogenous xanthine diluted the specific radioactivity of caffeine synthesized from [14C]adenine and [14C]hypoxanthine but caused accumulation of radiolabel in theobromine; (c) allopurinol, a known inhibitor of the conversion of hypoxanthine to xanthine, reduced incorporation of [14C]adenine and [14C]hypoxanthine into caffeine but caused accumulation of radiolabel in theobromine; and (d) incorporation of [14C]formate into caffeine, but not into theobromine, was reduced by added XMP, inosine, or hypoxanthine.

References

  1. Plant Physiol. 1983 Nov;73(3):766-72 - PubMed
  2. Plant Physiol. 1983 Aug;72(4):1029-34 - PubMed
  3. J Biol Chem. 1963 Oct;238:3344-7 - PubMed
  4. J Biol Chem. 1962 Jun;237:1941-4 - PubMed
  5. Biokhimiia. 1963 Sep-Oct;28:857-61 - PubMed
  6. Biochem J. 1975 Jan;146(1):79-85 - PubMed
  7. Biochem J. 1975 Jan;146(1):87-96 - PubMed
  8. Plant Physiol. 1979 Jan;63(1):100-4 - PubMed

Publication Types